12 lines
138 B
Racket
12 lines
138 B
Racket
#lang datalog/sexp
|
|
|
|
(! (sym a))
|
|
(! (sym b))
|
|
(! (sym c))
|
|
(! (:- (perm X Y)
|
|
(sym X)
|
|
(sym Y)
|
|
(!= X Y)))
|
|
|
|
(? (perm X Y))
|